"The American C-17 programme is open to all nations," Volker said in Berlin, referring to Boeing's Globemaster cargo aircraft.
European aviation company EADS in September was forced to postpone the maiden flight for the A400M indefinitely due to technical problems. The C-17 can carry double the load than the A400M, but it also costs twice as much as the European plane.
However, Volker said "a rather creative way" for Berlin to finance the craft would be for Germany to opt to lease the Boeing planes instead of purchasing them outright.
The German military currently is taking part in the NATO programme SALIS (Strategic Air Lift Interim Solution) until the A400M is ready for takeoff. SALIS has two Russian-made Antonov AN 124-100 cargo planes stationed at an airstrip near Leipzig that are ready for use within 72 hours for any of the countries participating in the programme.